COLOMBO , Sri Lanka -LRB- CNN -RRB- -- Sri Lanka 's government said Monday its forces had killed Tamil rebel chief Velupillai Prabhakaran as he attempted to flee , according to the country 's state-run news agency .

The Sri Lankan government says Tamil chief Velupillai Prabhakaran is dead .

The Tamil rebel group , formally known as the Liberation Tigers of Tamil Eelam -LRB- LTTE -RRB- , is aware of the government 's report but has yet to confirm Prabhakaran 's death or the deaths of its other leaders , according to a posting on the pro-rebel Web site , Tamilnet.com . It said `` initial reports indicate a determined massacre by the Sri Lanka Army . ''

Prabhakaran was one of 19 senior LTTE leaders that the government has identified among the bodies found as its troops completed mop-up operations after routing the Tigers , the defense ministry said .

The leaders include Prabhakaran 's eldest son , Charles Anthony , as well as Pottu Amman , LTTE 's intelligence leader , according to the ministry .

Prabhakaran founded the rebel group , which has been declared a terrorist organization by 32 countries . It pioneered the use of women in suicide attacks and , according to the FBI , invented the explosive suicide belt .

It was also behind the assassination of two world leaders -- the only terrorist organization to do so . Watch more on the possible end of fighting ''

Prabhakaran is accused of masterminding the killing of former Indian Prime Minister Rajiv Gandhi in 1991 in the Tamil-dominated Indian state of Tami Nadu as he campaigned for a second term . Sri Lankan authorities allege that Prabhakaran was avenging Gandhi 's decision to send Indian peacekeepers to Sri Lanka .

Two years later a Tigers suicide bomber , allegedly acting under Prabhakaran 's orders , detonated explosives that killed Sri Lanka 's then-president , Ranasinghe Premadasa , during a rally .

Over the weekend , the militants offered to `` silence '' their guns after an intense military offensive decimated their ranks , pushed them from their stronghold in the north and east of the country , and cornered the remaining rebels on a small stretch of land .

If the rebels honor their pledge , it would potentially mark the end of the longest-running civil war in Asia .

Prabhakaran 's supporters considered him a hero with a single-minded focus -- to fight for the rights of his people . The Sri Lankan government deemed him a war criminal with a disregard for civilian casualties . He was wanted by Interpol on charges including terrorism and organized crime .

In the past it has been reported he wore a cyanide capsule around his neck -- to swallow and kill himself rather than risk capture . And he reportedly expected the same dedication from his troops . As a result , few Tigers have been captured alive .

Sri Lanka 's President Mahinda Rajapaksa is expected to announce that `` military operations '' against the Tiger rebels have ended in an address to parliament and country on Tuesday . Watch aid agencies fear for Sri Lanka ''

The rebels have fought for an independent state for minority Tamils in Sri Lanka since July 1983 .

Journalist Iqbal Athas contributed to this report .

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Sri Lankan government says Tamil chief Velupillai Prabhakaran is dead

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The offensive against the rebel group is in its last stages , the government says

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Rebels have fought for an independent state for minority Tamils since 1983